diff --git a/pmd/etc/changelog.txt b/pmd/etc/changelog.txt
index 8c00028599..c0c11af3f0 100644
--- a/pmd/etc/changelog.txt
+++ b/pmd/etc/changelog.txt
@@ -1,6 +1,7 @@
 ???? - 4.2.4:
 
 Fixed bug 1481051 - false + UnusedNullCheckInEquals (and other false positives too)
+Fixed bug 1943204 - Ant task: <ruleset> path should be relative to Ant basedir
 
 August 31, 2008 - 4.2.3:
 
diff --git a/pmd/src/net/sourceforge/pmd/ant/PMDTask.java b/pmd/src/net/sourceforge/pmd/ant/PMDTask.java
index e6c145bc47..2cdc748a16 100644
--- a/pmd/src/net/sourceforge/pmd/ant/PMDTask.java
+++ b/pmd/src/net/sourceforge/pmd/ant/PMDTask.java
@@ -340,6 +340,18 @@ public class PMDTask extends Task {
             ruleSetFiles = getNestedRuleSetFiles();
         }
 
+        // convert relative paths and substitute env variables/properties
+        final StringBuffer sb = new StringBuffer();
+        for(String s: ruleSetFiles.split(",")) {
+            Path p = new Path(getProject());
+            p.setPath(getProject().replaceProperties(s));
+            if (sb.length() > 0) {
+                sb.append(',');
+            }
+            sb.append(p);
+        }
+        ruleSetFiles = sb.toString();
+
         if (!targetJDK.equals("1.3") && !targetJDK.equals("1.4") && !targetJDK.equals("1.5") && !targetJDK.equals("1.6") && !targetJDK.equals("1.7") && !targetJDK.equals("jsp")) {
             throw new BuildException("The targetjdk attribute, if used, must be set to either '1.3', '1.4', '1.5', '1.6', '1.7' or 'jsp'");
         }